* Re: [PATCH v4 1/2] module: add elf_check_module_arch for module specific elf arch checks
From: Segher Boessenkool @ 2021-06-15 12:50 UTC (permalink / raw)
To: Jessica Yu
Cc: Michal Suchánek, linuxppc-dev, linux-kernel, Nicholas Piggin
In-Reply-To: <YMiaZOqhHck9iy0n@p200300cbcf109700df096d564fe976c3.dip0.t-ipconnect.de>
On Tue, Jun 15, 2021 at 02:17:40PM +0200, Jessica Yu wrote:
> +int __weak elf_check_module_arch(Elf_Ehdr *hdr)
> +{
> + return 1;
> +}
But is this a good idea? It isn't useful to be able to attempt to load
a module not compiled for your architecture, and it increases the attack
surface tremendously. These checks are one of the few things that can
*not* be weak symbols, imo.
Segher
^ permalink raw reply
* switch the block layer to use kmap_local_page v2
From: Christoph Hellwig @ 2021-06-15 13:24 UTC (permalink / raw)
To: Jens Axboe, Thomas Gleixner
Cc: linux-arch, linux-block, Thomas Bogendoerfer, Mike Snitzer,
Geoff Levand, linuxppc-dev, linux-mips, Dongsheng Yang,
linux-kernel, James E.J. Bottomley, dm-devel, Ilya Dryomov,
Ira Weiny, ceph-devel
Hi all,
this series switches the core block layer code and all users of the
existing bvec kmap helpers to use kmap_local_page. Drivers that
currently use open coded kmap_atomic calls will converted in a follow
on series.
To do so a new kunmap variant is added that calls
flush_kernel_dcache_page. I'm not entirely sure where to call
flush_dcache_page vs flush_kernel_dcache_page, so I've tried to follow
the documentation here, but additional feedback would be welcome.
Changes since v1:
- add more/better comments
- add a new kunmap_local_dirty helper to feal with
flush(_kernel)_dcache_page
Diffstat:
arch/mips/include/asm/mach-rc32434/rb.h | 2 -
block/bio-integrity.c | 14 +++-----
block/bio.c | 37 ++++++----------------
block/blk-map.c | 2 -
block/bounce.c | 39 +++++-------------------
block/t10-pi.c | 16 +++------
drivers/block/ps3disk.c | 19 +----------
drivers/block/rbd.c | 15 +--------
drivers/md/dm-writecache.c | 5 +--
include/linux/bio.h | 42 -------------------------
include/linux/bvec.h | 52 ++++++++++++++++++++++++++++++--
include/linux/highmem-internal.h | 7 ++++
include/linux/highmem.h | 10 ++++--
13 files changed, 102 insertions(+), 158 deletions(-)
^ permalink raw reply
* [PATCH 01/18] mm: add a kunmap_local_dirty helper
From: Christoph Hellwig @ 2021-06-15 13:24 UTC (permalink / raw)
To: Jens Axboe, Thomas Gleixner
Cc: linux-arch, linux-block, Thomas Bogendoerfer, Mike Snitzer,
Geoff Levand, linuxppc-dev, linux-mips, Dongsheng Yang,
linux-kernel, James E.J. Bottomley, dm-devel, Ilya Dryomov,
Ira Weiny, ceph-devel
In-Reply-To: <20210615132456.753241-1-hch@lst.de>
Add a helper that calls flush_kernel_dcache_page before unmapping the
local mapping. flush_kernel_dcache_page is required for all pages
potentially mapped into userspace that were written to using kmap*,
so having a helper that does the right thing can be very convenient.
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
include/linux/highmem-internal.h | 7 +++++++
include/linux/highmem.h | 4 ++++
2 files changed, 11 insertions(+)
diff --git a/include/linux/highmem-internal.h b/include/linux/highmem-internal.h
index 7902c7d8b55f..bd37706db147 100644
--- a/include/linux/highmem-internal.h
+++ b/include/linux/highmem-internal.h
@@ -224,4 +224,11 @@ do { \
__kunmap_local(__addr); \
} while (0)
+#define kunmap_local_dirty(__page, __addr) \
+do { \
+ if (!PageSlab(__page)) \
+ flush_kernel_dcache_page(__page); \
+ kunmap_local(__addr); \
+} while (0)
+
#endif
diff --git a/include/linux/highmem.h b/include/linux/highmem.h
index 832b49b50c7b..65f548db4f2d 100644
--- a/include/linux/highmem.h
+++ b/include/linux/highmem.h
@@ -93,6 +93,10 @@ static inline void kmap_flush_unused(void);
* On HIGHMEM enabled systems mapping a highmem page has the side effect of
* disabling migration in order to keep the virtual address stable across
* preemption. No caller of kmap_local_page() can rely on this side effect.
+ *
+ * If data is written to the returned kernel mapping, the callers needs to
+ * unmap the mapping using kunmap_local_dirty(), else kunmap_local() should
+ * be used.
*/
static inline void *kmap_local_page(struct page *page);
--
2.30.2
^ permalink raw reply related
* [PATCH 02/18] mm: use kunmap_local_dirty in memcpy_to_page
From: Christoph Hellwig @ 2021-06-15 13:24 UTC (permalink / raw)
To: Jens Axboe, Thomas Gleixner
Cc: linux-arch, linux-block, Thomas Bogendoerfer, Mike Snitzer,
Geoff Levand, linuxppc-dev, linux-mips, Dongsheng Yang,
linux-kernel, James E.J. Bottomley, dm-devel, Ilya Dryomov,
Ira Weiny, ceph-devel
In-Reply-To: <20210615132456.753241-1-hch@lst.de>
memcpy_to_page can write to potentially mapped page cache pages, so
use kunmap_local_dirty to make sure flush_kernel_dcache_pages is
called.
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
include/linux/highmem.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/include/linux/highmem.h b/include/linux/highmem.h
index 65f548db4f2d..d0497c0daf80 100644
--- a/include/linux/highmem.h
+++ b/include/linux/highmem.h
@@ -333,7 +333,7 @@ static inline void memcpy_to_page(struct page *page, size_t offset,
VM_BUG_ON(offset + len > PAGE_SIZE);
memcpy(to + offset, from, len);
- kunmap_local(to);
+ kunmap_local_dirty(page, to);
}
static inline void memzero_page(struct page *page, size_t offset, size_t len)
--
2.30.2
^ permalink raw reply related
* [PATCH 03/18] mm: use kmap_local_page in memzero_page
From: Christoph Hellwig @ 2021-06-15 13:24 UTC (permalink / raw)
To: Jens Axboe, Thomas Gleixner
Cc: linux-arch, linux-block, Thomas Bogendoerfer, Chaitanya Kulkarni,
Mike Snitzer, Geoff Levand, linuxppc-dev, linux-mips,
Dongsheng Yang, linux-kernel, James E.J. Bottomley, dm-devel,
Ilya Dryomov, Ira Weiny, ceph-devel
In-Reply-To: <20210615132456.753241-1-hch@lst.de>
No need for kmap_atomic here.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
---
include/linux/highmem.h | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/include/linux/highmem.h b/include/linux/highmem.h
index d0497c0daf80..d3df0e2db44f 100644
--- a/include/linux/highmem.h
+++ b/include/linux/highmem.h
@@ -338,9 +338,9 @@ static inline void memcpy_to_page(struct page *page, size_t offset,
static inline void memzero_page(struct page *page, size_t offset, size_t len)
{
- char *addr = kmap_atomic(page);
+ char *addr = kmap_local_page(page);
memset(addr + offset, 0, len);
- kunmap_atomic(addr);
+ kunmap_local_dirty(page, addr);
}
#endif /* _LINUX_HIGHMEM_H */
--
2.30.2
^ permalink raw reply related
* [PATCH 04/18] MIPS: don't include <linux/genhd.h> in <asm/mach-rc32434/rb.h>
From: Christoph Hellwig @ 2021-06-15 13:24 UTC (permalink / raw)
To: Jens Axboe, Thomas Gleixner
Cc: linux-arch, linux-block, Thomas Bogendoerfer, Chaitanya Kulkarni,
Mike Snitzer, Geoff Levand, linuxppc-dev, linux-mips,
Dongsheng Yang, linux-kernel, James E.J. Bottomley, dm-devel,
Ilya Dryomov, Ira Weiny, ceph-devel
In-Reply-To: <20210615132456.753241-1-hch@lst.de>
There is no need to include genhd.h from a random arch header, and not
doing so prevents the possibility for nasty include loops.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
---
arch/mips/include/asm/mach-rc32434/rb.h | 2 --
1 file changed, 2 deletions(-)
diff --git a/arch/mips/include/asm/mach-rc32434/rb.h b/arch/mips/include/asm/mach-rc32434/rb.h
index d502673a4f6c..34d179ca020b 100644
--- a/arch/mips/include/asm/mach-rc32434/rb.h
+++ b/arch/mips/include/asm/mach-rc32434/rb.h
@@ -7,8 +7,6 @@
#ifndef __ASM_RC32434_RB_H
#define __ASM_RC32434_RB_H
-#include <linux/genhd.h>
-
#define REGBASE 0x18000000
#define IDT434_REG_BASE ((volatile void *) KSEG1ADDR(REGBASE))
#define UART0BASE 0x58000
--
2.30.2
^ permalink raw reply related
* [PATCH v10 00/12] Restricted DMA
From: Claire Chang @ 2021-06-15 13:26 UTC (permalink / raw)
To: Rob Herring, mpe, Joerg Roedel, Will Deacon, Frank Rowand,
Konrad Rzeszutek Wilk, boris.ostrovsky, jgross, Christoph Hellwig,
Marek Szyprowski
Cc: heikki.krogerus, thomas.hellstrom, peterz, joonas.lahtinen,
dri-devel, chris, grant.likely, paulus, mingo, jxgao, sstabellini,
Saravana Kannan, xypron.glpk, Rafael J . Wysocki,
Bartosz Golaszewski, bskeggs, linux-pci, xen-devel,
Thierry Reding, intel-gfx, matthew.auld, linux-devicetree, daniel,
airlied, maarten.lankhorst, linuxppc-dev, jani.nikula,
Nicolas Boichat, rodrigo.vivi, bhelgaas, tientzu, Dan Williams,
Andy Shevchenko, Greg KH, Randy Dunlap, lkml, tfiga,
list@263.net:IOMMU DRIVERS, Jim Quinlan, Robin Murphy, bauerman
This series implements mitigations for lack of DMA access control on
systems without an IOMMU, which could result in the DMA accessing the
system memory at unexpected times and/or unexpected addresses, possibly
leading to data leakage or corruption.
For example, we plan to use the PCI-e bus for Wi-Fi and that PCI-e bus is
not behind an IOMMU. As PCI-e, by design, gives the device full access to
system memory, a vulnerability in the Wi-Fi firmware could easily escalate
to a full system exploit (remote wifi exploits: [1a], [1b] that shows a
full chain of exploits; [2], [3]).
To mitigate the security concerns, we introduce restricted DMA. Restricted
DMA utilizes the existing swiotlb to bounce streaming DMA in and out of a
specially allocated region and does memory allocation from the same region.
The feature on its own provides a basic level of protection against the DMA
overwriting buffer contents at unexpected times. However, to protect
against general data leakage and system memory corruption, the system needs
to provide a way to restrict the DMA to a predefined memory region (this is
usually done at firmware level, e.g. MPU in ATF on some ARM platforms [4]).
[1a] https://googleprojectzero.blogspot.com/2017/04/over-air-exploiting-broadcoms-wi-fi_4.html
[1b] https://googleprojectzero.blogspot.com/2017/04/over-air-exploiting-broadcoms-wi-fi_11.html
[2] https://blade.tencent.com/en/advisories/qualpwn/
[3] https://www.bleepingcomputer.com/news/security/vulnerabilities-found-in-highly-popular-firmware-for-wifi-chips/
[4] https://github.com/ARM-software/arm-trusted-firmware/blob/master/plat/mediatek/mt8183/drivers/emi_mpu/emi_mpu.c#L132
v10:
Address the comments in v9 to
- fix the dev->dma_io_tlb_mem assignment
- propagate swiotlb_force setting into io_tlb_default_mem->force
- move set_memory_decrypted out of swiotlb_init_io_tlb_mem
- move debugfs_dir declaration into the main CONFIG_DEBUG_FS block
- add swiotlb_ prefix to find_slots and release_slots
- merge the 3 alloc/free related patches
- move the CONFIG_DMA_RESTRICTED_POOL later
v9:
Address the comments in v7 to
- set swiotlb active pool to dev->dma_io_tlb_mem
- get rid of get_io_tlb_mem
- dig out the device struct for is_swiotlb_active
- move debugfs_create_dir out of swiotlb_create_debugfs
- do set_memory_decrypted conditionally in swiotlb_init_io_tlb_mem
- use IS_ENABLED in kernel/dma/direct.c
- fix redefinition of 'of_dma_set_restricted_buffer'
https://lore.kernel.org/patchwork/cover/1445081/
v8:
- Fix reserved-memory.txt and add the reg property in example.
- Fix sizeof for of_property_count_elems_of_size in
drivers/of/address.c#of_dma_set_restricted_buffer.
- Apply Will's suggestion to try the OF node having DMA configuration in
drivers/of/address.c#of_dma_set_restricted_buffer.
- Fix typo in the comment of drivers/of/address.c#of_dma_set_restricted_buffer.
- Add error message for PageHighMem in
kernel/dma/swiotlb.c#rmem_swiotlb_device_init and move it to
rmem_swiotlb_setup.
- Fix the message string in rmem_swiotlb_setup.
https://lore.kernel.org/patchwork/cover/1437112/
v7:
Fix debugfs, PageHighMem and comment style in rmem_swiotlb_device_init
https://lore.kernel.org/patchwork/cover/1431031/
v6:
Address the comments in v5
https://lore.kernel.org/patchwork/cover/1423201/
v5:
Rebase on latest linux-next
https://lore.kernel.org/patchwork/cover/1416899/
v4:
- Fix spinlock bad magic
- Use rmem->name for debugfs entry
- Address the comments in v3
https://lore.kernel.org/patchwork/cover/1378113/
v3:
Using only one reserved memory region for both streaming DMA and memory
allocation.
https://lore.kernel.org/patchwork/cover/1360992/
v2:
Building on top of swiotlb.
https://lore.kernel.org/patchwork/cover/1280705/
v1:
Using dma_map_ops.
https://lore.kernel.org/patchwork/cover/1271660/
Claire Chang (12):
swiotlb: Refactor swiotlb init functions
swiotlb: Refactor swiotlb_create_debugfs
swiotlb: Set dev->dma_io_tlb_mem to the swiotlb pool used
swiotlb: Update is_swiotlb_buffer to add a struct device argument
swiotlb: Update is_swiotlb_active to add a struct device argument
swiotlb: Use is_dev_swiotlb_force for swiotlb data bouncing
swiotlb: Move alloc_size to swiotlb_find_slots
swiotlb: Refactor swiotlb_tbl_unmap_single
swiotlb: Add restricted DMA pool initialization
swiotlb: Add restricted DMA alloc/free support
dt-bindings: of: Add restricted DMA pool
of: Add plumbing for restricted DMA pool
.../reserved-memory/reserved-memory.txt | 36 ++-
drivers/base/core.c | 4 +
drivers/gpu/drm/i915/gem/i915_gem_internal.c | 2 +-
drivers/gpu/drm/nouveau/nouveau_ttm.c | 2 +-
drivers/iommu/dma-iommu.c | 12 +-
drivers/of/address.c | 33 +++
drivers/of/device.c | 3 +
drivers/of/of_private.h | 6 +
drivers/pci/xen-pcifront.c | 2 +-
drivers/xen/swiotlb-xen.c | 2 +-
include/linux/device.h | 4 +
include/linux/swiotlb.h | 40 ++-
kernel/dma/Kconfig | 14 +
kernel/dma/direct.c | 60 +++--
kernel/dma/direct.h | 8 +-
kernel/dma/swiotlb.c | 255 +++++++++++++-----
16 files changed, 380 insertions(+), 103 deletions(-)
--
2.32.0.272.g935e593368-goog
^ permalink raw reply
* [PATCH v10 01/12] swiotlb: Refactor swiotlb init functions
From: Claire Chang @ 2021-06-15 13:27 UTC (permalink / raw)
To: Rob Herring, mpe, Joerg Roedel, Will Deacon, Frank Rowand,
Konrad Rzeszutek Wilk, boris.ostrovsky, jgross, Christoph Hellwig,
Marek Szyprowski
Cc: heikki.krogerus, thomas.hellstrom, peterz, joonas.lahtinen,
dri-devel, chris, grant.likely, paulus, mingo, jxgao, sstabellini,
Saravana Kannan, xypron.glpk, Rafael J . Wysocki,
Bartosz Golaszewski, bskeggs, linux-pci, xen-devel,
Thierry Reding, intel-gfx, matthew.auld, linux-devicetree, daniel,
airlied, maarten.lankhorst, linuxppc-dev, jani.nikula,
Nicolas Boichat, rodrigo.vivi, bhelgaas, tientzu, Dan Williams,
Andy Shevchenko, Greg KH, Randy Dunlap, lkml, tfiga,
list@263.net:IOMMU DRIVERS, Jim Quinlan, Robin Murphy, bauerman
In-Reply-To: <20210615132711.553451-1-tientzu@chromium.org>
Add a new function, swiotlb_init_io_tlb_mem, for the io_tlb_mem struct
initialization to make the code reusable.
Signed-off-by: Claire Chang <tientzu@chromium.org>
---
kernel/dma/swiotlb.c | 49 ++++++++++++++++++++++----------------------
1 file changed, 24 insertions(+), 25 deletions(-)
diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
index 8ca7d505d61c..c64298e416c8 100644
--- a/kernel/dma/swiotlb.c
+++ b/kernel/dma/swiotlb.c
@@ -168,9 +168,28 @@ void __init swiotlb_update_mem_attributes(void)
memset(vaddr, 0, bytes);
}
-int __init swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose)
+static void swiotlb_init_io_tlb_mem(struct io_tlb_mem *mem, phys_addr_t start,
+ unsigned long nslabs, bool late_alloc)
{
+ void *vaddr = phys_to_virt(start);
unsigned long bytes = nslabs << IO_TLB_SHIFT, i;
+
+ mem->nslabs = nslabs;
+ mem->start = start;
+ mem->end = mem->start + bytes;
+ mem->index = 0;
+ mem->late_alloc = late_alloc;
+ spin_lock_init(&mem->lock);
+ for (i = 0; i < mem->nslabs; i++) {
+ mem->slots[i].list = IO_TLB_SEGSIZE - io_tlb_offset(i);
+ mem->slots[i].orig_addr = INVALID_PHYS_ADDR;
+ mem->slots[i].alloc_size = 0;
+ }
+ memset(vaddr, 0, bytes);
+}
+
+int __init swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose)
+{
struct io_tlb_mem *mem;
size_t alloc_size;
@@ -186,16 +205,8 @@ int __init swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose)
if (!mem)
panic("%s: Failed to allocate %zu bytes align=0x%lx\n",
__func__, alloc_size, PAGE_SIZE);
- mem->nslabs = nslabs;
- mem->start = __pa(tlb);
- mem->end = mem->start + bytes;
- mem->index = 0;
- spin_lock_init(&mem->lock);
- for (i = 0; i < mem->nslabs; i++) {
- mem->slots[i].list = IO_TLB_SEGSIZE - io_tlb_offset(i);
- mem->slots[i].orig_addr = INVALID_PHYS_ADDR;
- mem->slots[i].alloc_size = 0;
- }
+
+ swiotlb_init_io_tlb_mem(mem, __pa(tlb), nslabs, false);
io_tlb_default_mem = mem;
if (verbose)
@@ -282,8 +293,8 @@ swiotlb_late_init_with_default_size(size_t default_size)
int
swiotlb_late_init_with_tbl(char *tlb, unsigned long nslabs)
{
- unsigned long bytes = nslabs << IO_TLB_SHIFT, i;
struct io_tlb_mem *mem;
+ unsigned long bytes = nslabs << IO_TLB_SHIFT;
if (swiotlb_force == SWIOTLB_NO_FORCE)
return 0;
@@ -297,20 +308,8 @@ swiotlb_late_init_with_tbl(char *tlb, unsigned long nslabs)
if (!mem)
return -ENOMEM;
- mem->nslabs = nslabs;
- mem->start = virt_to_phys(tlb);
- mem->end = mem->start + bytes;
- mem->index = 0;
- mem->late_alloc = 1;
- spin_lock_init(&mem->lock);
- for (i = 0; i < mem->nslabs; i++) {
- mem->slots[i].list = IO_TLB_SEGSIZE - io_tlb_offset(i);
- mem->slots[i].orig_addr = INVALID_PHYS_ADDR;
- mem->slots[i].alloc_size = 0;
- }
-
+ swiotlb_init_io_tlb_mem(mem, virt_to_phys(tlb), nslabs, true);
set_memory_decrypted((unsigned long)tlb, bytes >> PAGE_SHIFT);
- memset(tlb, 0, bytes);
io_tlb_default_mem = mem;
swiotlb_print_info();
--
2.32.0.272.g935e593368-goog
^ permalink raw reply related
* [PATCH 05/18] bvec: fix the include guards for bvec.h
From: Christoph Hellwig @ 2021-06-15 13:24 UTC (permalink / raw)
To: Jens Axboe, Thomas Gleixner
Cc: linux-arch, linux-block, Thomas Bogendoerfer, Bart Van Assche,
Mike Snitzer, Geoff Levand, linuxppc-dev, Chaitanya Kulkarni,
linux-mips, Dongsheng Yang, linux-kernel, James E.J. Bottomley,
dm-devel, Ilya Dryomov, Ira Weiny, ceph-devel
In-Reply-To: <20210615132456.753241-1-hch@lst.de>
Fix the include guards to match the file naming.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
---
include/linux/bvec.h | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/include/linux/bvec.h b/include/linux/bvec.h
index ff832e698efb..883faf5f1523 100644
--- a/include/linux/bvec.h
+++ b/include/linux/bvec.h
@@ -4,8 +4,8 @@
*
* Copyright (C) 2001 Ming Lei <ming.lei@canonical.com>
*/
-#ifndef __LINUX_BVEC_ITER_H
-#define __LINUX_BVEC_ITER_H
+#ifndef __LINUX_BVEC_H
+#define __LINUX_BVEC_H
#include <linux/bug.h>
#include <linux/errno.h>
@@ -183,4 +183,4 @@ static inline void bvec_advance(const struct bio_vec *bvec,
}
}
-#endif /* __LINUX_BVEC_ITER_H */
+#endif /* __LINUX_BVEC_H */
--
2.30.2
^ permalink raw reply related
* [PATCH v10 02/12] swiotlb: Refactor swiotlb_create_debugfs
From: Claire Chang @ 2021-06-15 13:27 UTC (permalink / raw)
To: Rob Herring, mpe, Joerg Roedel, Will Deacon, Frank Rowand,
Konrad Rzeszutek Wilk, boris.ostrovsky, jgross, Christoph Hellwig,
Marek Szyprowski
Cc: heikki.krogerus, thomas.hellstrom, peterz, joonas.lahtinen,
dri-devel, chris, grant.likely, paulus, mingo, jxgao, sstabellini,
Saravana Kannan, xypron.glpk, Rafael J . Wysocki,
Bartosz Golaszewski, bskeggs, linux-pci, xen-devel,
Thierry Reding, intel-gfx, matthew.auld, linux-devicetree, daniel,
airlied, maarten.lankhorst, linuxppc-dev, jani.nikula,
Nicolas Boichat, rodrigo.vivi, bhelgaas, tientzu, Dan Williams,
Andy Shevchenko, Greg KH, Randy Dunlap, lkml, tfiga,
list@263.net:IOMMU DRIVERS, Jim Quinlan, Robin Murphy, bauerman
In-Reply-To: <20210615132711.553451-1-tientzu@chromium.org>
Split the debugfs creation to make the code reusable for supporting
different bounce buffer pools.
Signed-off-by: Claire Chang <tientzu@chromium.org>
---
kernel/dma/swiotlb.c | 21 ++++++++++++++-------
1 file changed, 14 insertions(+), 7 deletions(-)
diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
index c64298e416c8..97c6ad50fdc2 100644
--- a/kernel/dma/swiotlb.c
+++ b/kernel/dma/swiotlb.c
@@ -661,19 +661,26 @@ bool is_swiotlb_active(void)
EXPORT_SYMBOL_GPL(is_swiotlb_active);
#ifdef CONFIG_DEBUG_FS
+static struct dentry *debugfs_dir;
-static int __init swiotlb_create_debugfs(void)
+static void swiotlb_create_debugfs_files(struct io_tlb_mem *mem)
{
- struct io_tlb_mem *mem = io_tlb_default_mem;
-
- if (!mem)
- return 0;
- mem->debugfs = debugfs_create_dir("swiotlb", NULL);
debugfs_create_ulong("io_tlb_nslabs", 0400, mem->debugfs, &mem->nslabs);
debugfs_create_ulong("io_tlb_used", 0400, mem->debugfs, &mem->used);
+}
+
+static int __init swiotlb_create_default_debugfs(void)
+{
+ struct io_tlb_mem *mem = io_tlb_default_mem;
+
+ debugfs_dir = debugfs_create_dir("swiotlb", NULL);
+ if (mem) {
+ mem->debugfs = debugfs_dir;
+ swiotlb_create_debugfs_files(mem);
+ }
return 0;
}
-late_initcall(swiotlb_create_debugfs);
+late_initcall(swiotlb_create_default_debugfs);
#endif
--
2.32.0.272.g935e593368-goog
^ permalink raw reply related
* [PATCH v10 03/12] swiotlb: Set dev->dma_io_tlb_mem to the swiotlb pool used
From: Claire Chang @ 2021-06-15 13:27 UTC (permalink / raw)
To: Rob Herring, mpe, Joerg Roedel, Will Deacon, Frank Rowand,
Konrad Rzeszutek Wilk, boris.ostrovsky, jgross, Christoph Hellwig,
Marek Szyprowski
Cc: heikki.krogerus, thomas.hellstrom, peterz, joonas.lahtinen,
dri-devel, chris, grant.likely, paulus, mingo, jxgao, sstabellini,
Saravana Kannan, xypron.glpk, Rafael J . Wysocki,
Bartosz Golaszewski, bskeggs, linux-pci, xen-devel,
Thierry Reding, intel-gfx, matthew.auld, linux-devicetree, daniel,
airlied, maarten.lankhorst, linuxppc-dev, jani.nikula,
Nicolas Boichat, rodrigo.vivi, bhelgaas, tientzu, Dan Williams,
Andy Shevchenko, Greg KH, Randy Dunlap, lkml, tfiga,
list@263.net:IOMMU DRIVERS, Jim Quinlan, Robin Murphy, bauerman
In-Reply-To: <20210615132711.553451-1-tientzu@chromium.org>
Always have the pointer to the swiotlb pool used in struct device. This
could help simplify the code for other pools.
Signed-off-by: Claire Chang <tientzu@chromium.org>
---
drivers/base/core.c | 4 ++++
include/linux/device.h | 4 ++++
kernel/dma/swiotlb.c | 8 ++++----
3 files changed, 12 insertions(+), 4 deletions(-)
diff --git a/drivers/base/core.c b/drivers/base/core.c
index b8a8c96dca58..eeb2d49d3aa3 100644
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -27,6 +27,7 @@
#include <linux/netdevice.h>
#include <linux/sched/signal.h>
#include <linux/sched/mm.h>
+#include <linux/swiotlb.h>
#include <linux/sysfs.h>
#include <linux/dma-map-ops.h> /* for dma_default_coherent */
@@ -2846,6 +2847,9 @@ void device_initialize(struct device *dev)
defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU_ALL)
dev->dma_coherent = dma_default_coherent;
#endif
+#ifdef CONFIG_SWIOTLB
+ dev->dma_io_tlb_mem = io_tlb_default_mem;
+#endif
}
EXPORT_SYMBOL_GPL(device_initialize);
diff --git a/include/linux/device.h b/include/linux/device.h
index 4443e12238a0..2e9a378c9100 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -432,6 +432,7 @@ struct dev_links_info {
* @dma_pools: Dma pools (if dma'ble device).
* @dma_mem: Internal for coherent mem override.
* @cma_area: Contiguous memory area for dma allocations
+ * @dma_io_tlb_mem: Pointer to the swiotlb pool used. Not for driver use.
* @archdata: For arch-specific additions.
* @of_node: Associated device tree node.
* @fwnode: Associated device node supplied by platform firmware.
@@ -540,6 +541,9 @@ struct device {
#ifdef CONFIG_DMA_CMA
struct cma *cma_area; /* contiguous memory area for dma
allocations */
+#endif
+#ifdef CONFIG_SWIOTLB
+ struct io_tlb_mem *dma_io_tlb_mem;
#endif
/* arch specific additions */
struct dev_archdata archdata;
diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
index 97c6ad50fdc2..949a6bb21343 100644
--- a/kernel/dma/swiotlb.c
+++ b/kernel/dma/swiotlb.c
@@ -339,7 +339,7 @@ void __init swiotlb_exit(void)
static void swiotlb_bounce(struct device *dev, phys_addr_t tlb_addr, size_t size,
enum dma_data_direction dir)
{
- struct io_tlb_mem *mem = io_tlb_default_mem;
+ struct io_tlb_mem *mem = dev->dma_io_tlb_mem;
int index = (tlb_addr - mem->start) >> IO_TLB_SHIFT;
phys_addr_t orig_addr = mem->slots[index].orig_addr;
size_t alloc_size = mem->slots[index].alloc_size;
@@ -421,7 +421,7 @@ static unsigned int wrap_index(struct io_tlb_mem *mem, unsigned int index)
static int find_slots(struct device *dev, phys_addr_t orig_addr,
size_t alloc_size)
{
- struct io_tlb_mem *mem = io_tlb_default_mem;
+ struct io_tlb_mem *mem = dev->dma_io_tlb_mem;
unsigned long boundary_mask = dma_get_seg_boundary(dev);
dma_addr_t tbl_dma_addr =
phys_to_dma_unencrypted(dev, mem->start) & boundary_mask;
@@ -498,7 +498,7 @@ phys_addr_t swiotlb_tbl_map_single(struct device *dev, phys_addr_t orig_addr,
size_t mapping_size, size_t alloc_size,
enum dma_data_direction dir, unsigned long attrs)
{
- struct io_tlb_mem *mem = io_tlb_default_mem;
+ struct io_tlb_mem *mem = dev->dma_io_tlb_mem;
unsigned int offset = swiotlb_align_offset(dev, orig_addr);
unsigned int i;
int index;
@@ -549,7 +549,7 @@ void swiotlb_tbl_unmap_single(struct device *hwdev, phys_addr_t tlb_addr,
size_t mapping_size, enum dma_data_direction dir,
unsigned long attrs)
{
- struct io_tlb_mem *mem = io_tlb_default_mem;
+ struct io_tlb_mem *mem = hwdev->dma_io_tlb_mem;
unsigned long flags;
unsigned int offset = swiotlb_align_offset(hwdev, tlb_addr);
int index = (tlb_addr - offset - mem->start) >> IO_TLB_SHIFT;
--
2.32.0.272.g935e593368-goog
^ permalink raw reply related
* [PATCH v10 04/12] swiotlb: Update is_swiotlb_buffer to add a struct device argument
From: Claire Chang @ 2021-06-15 13:27 UTC (permalink / raw)
To: Rob Herring, mpe, Joerg Roedel, Will Deacon, Frank Rowand,
Konrad Rzeszutek Wilk, boris.ostrovsky, jgross, Christoph Hellwig,
Marek Szyprowski
Cc: heikki.krogerus, thomas.hellstrom, peterz, joonas.lahtinen,
dri-devel, chris, grant.likely, paulus, mingo, jxgao, sstabellini,
Saravana Kannan, xypron.glpk, Rafael J . Wysocki,
Bartosz Golaszewski, bskeggs, linux-pci, xen-devel,
Thierry Reding, intel-gfx, matthew.auld, linux-devicetree, daniel,
airlied, maarten.lankhorst, linuxppc-dev, jani.nikula,
Nicolas Boichat, rodrigo.vivi, bhelgaas, tientzu, Dan Williams,
Andy Shevchenko, Greg KH, Randy Dunlap, lkml, tfiga,
list@263.net:IOMMU DRIVERS, Jim Quinlan, Robin Murphy, bauerman
In-Reply-To: <20210615132711.553451-1-tientzu@chromium.org>
Update is_swiotlb_buffer to add a struct device argument. This will be
useful later to allow for different pools.
Signed-off-by: Claire Chang <tientzu@chromium.org>
---
drivers/iommu/dma-iommu.c | 12 ++++++------
drivers/xen/swiotlb-xen.c | 2 +-
include/linux/swiotlb.h | 7 ++++---
kernel/dma/direct.c | 6 +++---
kernel/dma/direct.h | 6 +++---
5 files changed, 17 insertions(+), 16 deletions(-)
diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c
index 5d96fcc45fec..1a6a08908245 100644
--- a/drivers/iommu/dma-iommu.c
+++ b/drivers/iommu/dma-iommu.c
@@ -506,7 +506,7 @@ static void __iommu_dma_unmap_swiotlb(struct device *dev, dma_addr_t dma_addr,
__iommu_dma_unmap(dev, dma_addr, size);
- if (unlikely(is_swiotlb_buffer(phys)))
+ if (unlikely(is_swiotlb_buffer(dev, phys)))
swiotlb_tbl_unmap_single(dev, phys, size, dir, attrs);
}
@@ -577,7 +577,7 @@ static dma_addr_t __iommu_dma_map_swiotlb(struct device *dev, phys_addr_t phys,
}
iova = __iommu_dma_map(dev, phys, aligned_size, prot, dma_mask);
- if (iova == DMA_MAPPING_ERROR && is_swiotlb_buffer(phys))
+ if (iova == DMA_MAPPING_ERROR && is_swiotlb_buffer(dev, phys))
swiotlb_tbl_unmap_single(dev, phys, org_size, dir, attrs);
return iova;
}
@@ -783,7 +783,7 @@ static void iommu_dma_sync_single_for_cpu(struct device *dev,
if (!dev_is_dma_coherent(dev))
arch_sync_dma_for_cpu(phys, size, dir);
- if (is_swiotlb_buffer(phys))
+ if (is_swiotlb_buffer(dev, phys))
swiotlb_sync_single_for_cpu(dev, phys, size, dir);
}
@@ -796,7 +796,7 @@ static void iommu_dma_sync_single_for_device(struct device *dev,
return;
phys = iommu_iova_to_phys(iommu_get_dma_domain(dev), dma_handle);
- if (is_swiotlb_buffer(phys))
+ if (is_swiotlb_buffer(dev, phys))
swiotlb_sync_single_for_device(dev, phys, size, dir);
if (!dev_is_dma_coherent(dev))
@@ -817,7 +817,7 @@ static void iommu_dma_sync_sg_for_cpu(struct device *dev,
if (!dev_is_dma_coherent(dev))
arch_sync_dma_for_cpu(sg_phys(sg), sg->length, dir);
- if (is_swiotlb_buffer(sg_phys(sg)))
+ if (is_swiotlb_buffer(dev, sg_phys(sg)))
swiotlb_sync_single_for_cpu(dev, sg_phys(sg),
sg->length, dir);
}
@@ -834,7 +834,7 @@ static void iommu_dma_sync_sg_for_device(struct device *dev,
return;
for_each_sg(sgl, sg, nelems, i) {
- if (is_swiotlb_buffer(sg_phys(sg)))
+ if (is_swiotlb_buffer(dev, sg_phys(sg)))
swiotlb_sync_single_for_device(dev, sg_phys(sg),
sg->length, dir);
diff --git a/drivers/xen/swiotlb-xen.c b/drivers/xen/swiotlb-xen.c
index 24d11861ac7d..0c4fb34f11ab 100644
--- a/drivers/xen/swiotlb-xen.c
+++ b/drivers/xen/swiotlb-xen.c
@@ -100,7 +100,7 @@ static int is_xen_swiotlb_buffer(struct device *dev, dma_addr_t dma_addr)
* in our domain. Therefore _only_ check address within our domain.
*/
if (pfn_valid(PFN_DOWN(paddr)))
- return is_swiotlb_buffer(paddr);
+ return is_swiotlb_buffer(dev, paddr);
return 0;
}
diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h
index 216854a5e513..d1f3d95881cd 100644
--- a/include/linux/swiotlb.h
+++ b/include/linux/swiotlb.h
@@ -2,6 +2,7 @@
#ifndef __LINUX_SWIOTLB_H
#define __LINUX_SWIOTLB_H
+#include <linux/device.h>
#include <linux/dma-direction.h>
#include <linux/init.h>
#include <linux/types.h>
@@ -101,9 +102,9 @@ struct io_tlb_mem {
};
extern struct io_tlb_mem *io_tlb_default_mem;
-static inline bool is_swiotlb_buffer(phys_addr_t paddr)
+static inline bool is_swiotlb_buffer(struct device *dev, phys_addr_t paddr)
{
- struct io_tlb_mem *mem = io_tlb_default_mem;
+ struct io_tlb_mem *mem = dev->dma_io_tlb_mem;
return mem && paddr >= mem->start && paddr < mem->end;
}
@@ -115,7 +116,7 @@ bool is_swiotlb_active(void);
void __init swiotlb_adjust_size(unsigned long size);
#else
#define swiotlb_force SWIOTLB_NO_FORCE
-static inline bool is_swiotlb_buffer(phys_addr_t paddr)
+static inline bool is_swiotlb_buffer(struct device *dev, phys_addr_t paddr)
{
return false;
}
diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c
index f737e3347059..84c9feb5474a 100644
--- a/kernel/dma/direct.c
+++ b/kernel/dma/direct.c
@@ -343,7 +343,7 @@ void dma_direct_sync_sg_for_device(struct device *dev,
for_each_sg(sgl, sg, nents, i) {
phys_addr_t paddr = dma_to_phys(dev, sg_dma_address(sg));
- if (unlikely(is_swiotlb_buffer(paddr)))
+ if (unlikely(is_swiotlb_buffer(dev, paddr)))
swiotlb_sync_single_for_device(dev, paddr, sg->length,
dir);
@@ -369,7 +369,7 @@ void dma_direct_sync_sg_for_cpu(struct device *dev,
if (!dev_is_dma_coherent(dev))
arch_sync_dma_for_cpu(paddr, sg->length, dir);
- if (unlikely(is_swiotlb_buffer(paddr)))
+ if (unlikely(is_swiotlb_buffer(dev, paddr)))
swiotlb_sync_single_for_cpu(dev, paddr, sg->length,
dir);
@@ -504,7 +504,7 @@ size_t dma_direct_max_mapping_size(struct device *dev)
bool dma_direct_need_sync(struct device *dev, dma_addr_t dma_addr)
{
return !dev_is_dma_coherent(dev) ||
- is_swiotlb_buffer(dma_to_phys(dev, dma_addr));
+ is_swiotlb_buffer(dev, dma_to_phys(dev, dma_addr));
}
/**
diff --git a/kernel/dma/direct.h b/kernel/dma/direct.h
index 50afc05b6f1d..13e9e7158d94 100644
--- a/kernel/dma/direct.h
+++ b/kernel/dma/direct.h
@@ -56,7 +56,7 @@ static inline void dma_direct_sync_single_for_device(struct device *dev,
{
phys_addr_t paddr = dma_to_phys(dev, addr);
- if (unlikely(is_swiotlb_buffer(paddr)))
+ if (unlikely(is_swiotlb_buffer(dev, paddr)))
swiotlb_sync_single_for_device(dev, paddr, size, dir);
if (!dev_is_dma_coherent(dev))
@@ -73,7 +73,7 @@ static inline void dma_direct_sync_single_for_cpu(struct device *dev,
arch_sync_dma_for_cpu_all();
}
- if (unlikely(is_swiotlb_buffer(paddr)))
+ if (unlikely(is_swiotlb_buffer(dev, paddr)))
swiotlb_sync_single_for_cpu(dev, paddr, size, dir);
if (dir == DMA_FROM_DEVICE)
@@ -113,7 +113,7 @@ static inline void dma_direct_unmap_page(struct device *dev, dma_addr_t addr,
if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
dma_direct_sync_single_for_cpu(dev, addr, size, dir);
- if (unlikely(is_swiotlb_buffer(phys)))
+ if (unlikely(is_swiotlb_buffer(dev, phys)))
swiotlb_tbl_unmap_single(dev, phys, size, dir, attrs);
}
#endif /* _KERNEL_DMA_DIRECT_H */
--
2.32.0.272.g935e593368-goog
^ permalink raw reply related
* [PATCH 06/18] bvec: add a bvec_kmap_local helper
From: Christoph Hellwig @ 2021-06-15 13:24 UTC (permalink / raw)
To: Jens Axboe, Thomas Gleixner
Cc: linux-arch, linux-block, Thomas Bogendoerfer, Chaitanya Kulkarni,
Mike Snitzer, Geoff Levand, linuxppc-dev, linux-mips,
Dongsheng Yang, linux-kernel, James E.J. Bottomley, dm-devel,
Ilya Dryomov, Ira Weiny, ceph-devel
In-Reply-To: <20210615132456.753241-1-hch@lst.de>
Add a helper to call kmap_local_page on a bvec. There is no need for
an unmap helper given that kunmap_local accept any address in the mapped
page.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
---
include/linux/bvec.h | 13 +++++++++++++
1 file changed, 13 insertions(+)
diff --git a/include/linux/bvec.h b/include/linux/bvec.h
index 883faf5f1523..f8710af18eef 100644
--- a/include/linux/bvec.h
+++ b/include/linux/bvec.h
@@ -7,6 +7,7 @@
#ifndef __LINUX_BVEC_H
#define __LINUX_BVEC_H
+#include <linux/highmem.h>
#include <linux/bug.h>
#include <linux/errno.h>
#include <linux/limits.h>
@@ -183,4 +184,16 @@ static inline void bvec_advance(const struct bio_vec *bvec,
}
}
+/**
+ * bvec_kmap_local - map a bvec into the kernel virtual address space
+ * @bvec: bvec to map
+ *
+ * Must be called on single-page bvecs only. Call kunmap_local on the returned
+ * address to unmap.
+ */
+static inline void *bvec_kmap_local(struct bio_vec *bvec)
+{
+ return kmap_local_page(bvec->bv_page) + bvec->bv_offset;
+}
+
#endif /* __LINUX_BVEC_H */
--
2.30.2
^ permalink raw reply related
* [PATCH v10 05/12] swiotlb: Update is_swiotlb_active to add a struct device argument
From: Claire Chang @ 2021-06-15 13:27 UTC (permalink / raw)
To: Rob Herring, mpe, Joerg Roedel, Will Deacon, Frank Rowand,
Konrad Rzeszutek Wilk, boris.ostrovsky, jgross, Christoph Hellwig,
Marek Szyprowski
Cc: heikki.krogerus, thomas.hellstrom, peterz, joonas.lahtinen,
dri-devel, chris, grant.likely, paulus, mingo, jxgao, sstabellini,
Saravana Kannan, xypron.glpk, Rafael J . Wysocki,
Bartosz Golaszewski, bskeggs, linux-pci, xen-devel,
Thierry Reding, intel-gfx, matthew.auld, linux-devicetree, daniel,
airlied, maarten.lankhorst, linuxppc-dev, jani.nikula,
Nicolas Boichat, rodrigo.vivi, bhelgaas, tientzu, Dan Williams,
Andy Shevchenko, Greg KH, Randy Dunlap, lkml, tfiga,
list@263.net:IOMMU DRIVERS, Jim Quinlan, Robin Murphy, bauerman
In-Reply-To: <20210615132711.553451-1-tientzu@chromium.org>
Update is_swiotlb_active to add a struct device argument. This will be
useful later to allow for different pools.
Signed-off-by: Claire Chang <tientzu@chromium.org>
---
drivers/gpu/drm/i915/gem/i915_gem_internal.c | 2 +-
drivers/gpu/drm/nouveau/nouveau_ttm.c | 2 +-
drivers/pci/xen-pcifront.c | 2 +-
include/linux/swiotlb.h | 4 ++--
kernel/dma/direct.c | 2 +-
kernel/dma/swiotlb.c | 4 ++--
6 files changed, 8 insertions(+), 8 deletions(-)
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_internal.c b/drivers/gpu/drm/i915/gem/i915_gem_internal.c
index ce6b664b10aa..89a894354263 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_internal.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_internal.c
@@ -42,7 +42,7 @@ static int i915_gem_object_get_pages_internal(struct drm_i915_gem_object *obj)
max_order = MAX_ORDER;
#ifdef CONFIG_SWIOTLB
- if (is_swiotlb_active()) {
+ if (is_swiotlb_active(obj->base.dev->dev)) {
unsigned int max_segment;
max_segment = swiotlb_max_segment();
diff --git a/drivers/gpu/drm/nouveau/nouveau_ttm.c b/drivers/gpu/drm/nouveau/nouveau_ttm.c
index f4c2e46b6fe1..2ca9d9a9e5d5 100644
--- a/drivers/gpu/drm/nouveau/nouveau_ttm.c
+++ b/drivers/gpu/drm/nouveau/nouveau_ttm.c
@@ -276,7 +276,7 @@ nouveau_ttm_init(struct nouveau_drm *drm)
}
#if IS_ENABLED(CONFIG_SWIOTLB) && IS_ENABLED(CONFIG_X86)
- need_swiotlb = is_swiotlb_active();
+ need_swiotlb = is_swiotlb_active(dev->dev);
#endif
ret = ttm_device_init(&drm->ttm.bdev, &nouveau_bo_driver, drm->dev->dev,
diff --git a/drivers/pci/xen-pcifront.c b/drivers/pci/xen-pcifront.c
index b7a8f3a1921f..0d56985bfe81 100644
--- a/drivers/pci/xen-pcifront.c
+++ b/drivers/pci/xen-pcifront.c
@@ -693,7 +693,7 @@ static int pcifront_connect_and_init_dma(struct pcifront_device *pdev)
spin_unlock(&pcifront_dev_lock);
- if (!err && !is_swiotlb_active()) {
+ if (!err && !is_swiotlb_active(&pdev->xdev->dev)) {
err = pci_xen_swiotlb_init_late();
if (err)
dev_err(&pdev->xdev->dev, "Could not setup SWIOTLB!\n");
diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h
index d1f3d95881cd..dd1c30a83058 100644
--- a/include/linux/swiotlb.h
+++ b/include/linux/swiotlb.h
@@ -112,7 +112,7 @@ static inline bool is_swiotlb_buffer(struct device *dev, phys_addr_t paddr)
void __init swiotlb_exit(void);
unsigned int swiotlb_max_segment(void);
size_t swiotlb_max_mapping_size(struct device *dev);
-bool is_swiotlb_active(void);
+bool is_swiotlb_active(struct device *dev);
void __init swiotlb_adjust_size(unsigned long size);
#else
#define swiotlb_force SWIOTLB_NO_FORCE
@@ -132,7 +132,7 @@ static inline size_t swiotlb_max_mapping_size(struct device *dev)
return SIZE_MAX;
}
-static inline bool is_swiotlb_active(void)
+static inline bool is_swiotlb_active(struct device *dev)
{
return false;
}
diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c
index 84c9feb5474a..7a88c34d0867 100644
--- a/kernel/dma/direct.c
+++ b/kernel/dma/direct.c
@@ -495,7 +495,7 @@ int dma_direct_supported(struct device *dev, u64 mask)
size_t dma_direct_max_mapping_size(struct device *dev)
{
/* If SWIOTLB is active, use its maximum mapping size */
- if (is_swiotlb_active() &&
+ if (is_swiotlb_active(dev) &&
(dma_addressing_limited(dev) || swiotlb_force == SWIOTLB_FORCE))
return swiotlb_max_mapping_size(dev);
return SIZE_MAX;
diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
index 949a6bb21343..d07e32020edf 100644
--- a/kernel/dma/swiotlb.c
+++ b/kernel/dma/swiotlb.c
@@ -654,9 +654,9 @@ size_t swiotlb_max_mapping_size(struct device *dev)
return ((size_t)IO_TLB_SIZE) * IO_TLB_SEGSIZE;
}
-bool is_swiotlb_active(void)
+bool is_swiotlb_active(struct device *dev)
{
- return io_tlb_default_mem != NULL;
+ return dev->dma_io_tlb_mem != NULL;
}
EXPORT_SYMBOL_GPL(is_swiotlb_active);
--
2.32.0.272.g935e593368-goog
^ permalink raw reply related
* [PATCH v10 06/12] swiotlb: Use is_dev_swiotlb_force for swiotlb data bouncing
From: Claire Chang @ 2021-06-15 13:27 UTC (permalink / raw)
To: Rob Herring, mpe, Joerg Roedel, Will Deacon, Frank Rowand,
Konrad Rzeszutek Wilk, boris.ostrovsky, jgross, Christoph Hellwig,
Marek Szyprowski
Cc: heikki.krogerus, thomas.hellstrom, peterz, joonas.lahtinen,
dri-devel, chris, grant.likely, paulus, mingo, jxgao, sstabellini,
Saravana Kannan, xypron.glpk, Rafael J . Wysocki,
Bartosz Golaszewski, bskeggs, linux-pci, xen-devel,
Thierry Reding, intel-gfx, matthew.auld, linux-devicetree, daniel,
airlied, maarten.lankhorst, linuxppc-dev, jani.nikula,
Nicolas Boichat, rodrigo.vivi, bhelgaas, tientzu, Dan Williams,
Andy Shevchenko, Greg KH, Randy Dunlap, lkml, tfiga,
list@263.net:IOMMU DRIVERS, Jim Quinlan, Robin Murphy, bauerman
In-Reply-To: <20210615132711.553451-1-tientzu@chromium.org>
Propagate the swiotlb_force setting into io_tlb_default_mem->force and
use it to determine whether to bounce the data or not. This will be
useful later to allow for different pools.
Signed-off-by: Claire Chang <tientzu@chromium.org>
---
include/linux/swiotlb.h | 11 +++++++++++
kernel/dma/direct.c | 2 +-
kernel/dma/direct.h | 2 +-
kernel/dma/swiotlb.c | 4 ++++
4 files changed, 17 insertions(+), 2 deletions(-)
diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h
index dd1c30a83058..efcd56e3a16c 100644
--- a/include/linux/swiotlb.h
+++ b/include/linux/swiotlb.h
@@ -84,6 +84,7 @@ extern enum swiotlb_force swiotlb_force;
* unmap calls.
* @debugfs: The dentry to debugfs.
* @late_alloc: %true if allocated using the page allocator
+ * @force: %true if swiotlb is forced
*/
struct io_tlb_mem {
phys_addr_t start;
@@ -94,6 +95,7 @@ struct io_tlb_mem {
spinlock_t lock;
struct dentry *debugfs;
bool late_alloc;
+ bool force;
struct io_tlb_slot {
phys_addr_t orig_addr;
size_t alloc_size;
@@ -109,6 +111,11 @@ static inline bool is_swiotlb_buffer(struct device *dev, phys_addr_t paddr)
return mem && paddr >= mem->start && paddr < mem->end;
}
+static inline bool is_dev_swiotlb_force(struct device *dev)
+{
+ return dev->dma_io_tlb_mem->force;
+}
+
void __init swiotlb_exit(void);
unsigned int swiotlb_max_segment(void);
size_t swiotlb_max_mapping_size(struct device *dev);
@@ -120,6 +127,10 @@ static inline bool is_swiotlb_buffer(struct device *dev, phys_addr_t paddr)
{
return false;
}
+static inline bool is_dev_swiotlb_force(struct device *dev)
+{
+ return false;
+}
static inline void swiotlb_exit(void)
{
}
diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c
index 7a88c34d0867..3713461d6fe0 100644
--- a/kernel/dma/direct.c
+++ b/kernel/dma/direct.c
@@ -496,7 +496,7 @@ size_t dma_direct_max_mapping_size(struct device *dev)
{
/* If SWIOTLB is active, use its maximum mapping size */
if (is_swiotlb_active(dev) &&
- (dma_addressing_limited(dev) || swiotlb_force == SWIOTLB_FORCE))
+ (dma_addressing_limited(dev) || is_dev_swiotlb_force(dev)))
return swiotlb_max_mapping_size(dev);
return SIZE_MAX;
}
diff --git a/kernel/dma/direct.h b/kernel/dma/direct.h
index 13e9e7158d94..6c4d13caceb1 100644
--- a/kernel/dma/direct.h
+++ b/kernel/dma/direct.h
@@ -87,7 +87,7 @@ static inline dma_addr_t dma_direct_map_page(struct device *dev,
phys_addr_t phys = page_to_phys(page) + offset;
dma_addr_t dma_addr = phys_to_dma(dev, phys);
- if (unlikely(swiotlb_force == SWIOTLB_FORCE))
+ if (is_dev_swiotlb_force(dev))
return swiotlb_map(dev, phys, size, dir, attrs);
if (unlikely(!dma_capable(dev, dma_addr, size, true))) {
diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
index d07e32020edf..5af47a8f68b8 100644
--- a/kernel/dma/swiotlb.c
+++ b/kernel/dma/swiotlb.c
@@ -179,6 +179,10 @@ static void swiotlb_init_io_tlb_mem(struct io_tlb_mem *mem, phys_addr_t start,
mem->end = mem->start + bytes;
mem->index = 0;
mem->late_alloc = late_alloc;
+
+ if (swiotlb_force == SWIOTLB_FORCE)
+ mem->force = true;
+
spin_lock_init(&mem->lock);
for (i = 0; i < mem->nslabs; i++) {
mem->slots[i].list = IO_TLB_SEGSIZE - io_tlb_offset(i);
--
2.32.0.272.g935e593368-goog
^ permalink raw reply related
* [PATCH v10 07/12] swiotlb: Move alloc_size to swiotlb_find_slots
From: Claire Chang @ 2021-06-15 13:27 UTC (permalink / raw)
To: Rob Herring, mpe, Joerg Roedel, Will Deacon, Frank Rowand,
Konrad Rzeszutek Wilk, boris.ostrovsky, jgross, Christoph Hellwig,
Marek Szyprowski
Cc: heikki.krogerus, thomas.hellstrom, peterz, joonas.lahtinen,
dri-devel, chris, grant.likely, paulus, mingo, jxgao, sstabellini,
Saravana Kannan, xypron.glpk, Rafael J . Wysocki,
Bartosz Golaszewski, bskeggs, linux-pci, xen-devel,
Thierry Reding, intel-gfx, matthew.auld, linux-devicetree, daniel,
airlied, maarten.lankhorst, linuxppc-dev, jani.nikula,
Nicolas Boichat, rodrigo.vivi, bhelgaas, tientzu, Dan Williams,
Andy Shevchenko, Greg KH, Randy Dunlap, lkml, tfiga,
list@263.net:IOMMU DRIVERS, Jim Quinlan, Robin Murphy, bauerman
In-Reply-To: <20210615132711.553451-1-tientzu@chromium.org>
Rename find_slots to swiotlb_find_slots and move the maintenance of
alloc_size to it for better code reusability later.
Signed-off-by: Claire Chang <tientzu@chromium.org>
---
kernel/dma/swiotlb.c | 16 ++++++++--------
1 file changed, 8 insertions(+), 8 deletions(-)
diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
index 5af47a8f68b8..e498f11e150e 100644
--- a/kernel/dma/swiotlb.c
+++ b/kernel/dma/swiotlb.c
@@ -422,8 +422,8 @@ static unsigned int wrap_index(struct io_tlb_mem *mem, unsigned int index)
* Find a suitable number of IO TLB entries size that will fit this request and
* allocate a buffer from that IO TLB pool.
*/
-static int find_slots(struct device *dev, phys_addr_t orig_addr,
- size_t alloc_size)
+static int swiotlb_find_slots(struct device *dev, phys_addr_t orig_addr,
+ size_t alloc_size)
{
struct io_tlb_mem *mem = dev->dma_io_tlb_mem;
unsigned long boundary_mask = dma_get_seg_boundary(dev);
@@ -478,8 +478,11 @@ static int find_slots(struct device *dev, phys_addr_t orig_addr,
return -1;
found:
- for (i = index; i < index + nslots; i++)
+ for (i = index; i < index + nslots; i++) {
mem->slots[i].list = 0;
+ mem->slots[i].alloc_size =
+ alloc_size - ((i - index) << IO_TLB_SHIFT);
+ }
for (i = index - 1;
io_tlb_offset(i) != IO_TLB_SEGSIZE - 1 &&
mem->slots[i].list; i--)
@@ -520,7 +523,7 @@ phys_addr_t swiotlb_tbl_map_single(struct device *dev, phys_addr_t orig_addr,
return (phys_addr_t)DMA_MAPPING_ERROR;
}
- index = find_slots(dev, orig_addr, alloc_size + offset);
+ index = swiotlb_find_slots(dev, orig_addr, alloc_size + offset);
if (index == -1) {
if (!(attrs & DMA_ATTR_NO_WARN))
dev_warn_ratelimited(dev,
@@ -534,11 +537,8 @@ phys_addr_t swiotlb_tbl_map_single(struct device *dev, phys_addr_t orig_addr,
* This is needed when we sync the memory. Then we sync the buffer if
* needed.
*/
- for (i = 0; i < nr_slots(alloc_size + offset); i++) {
+ for (i = 0; i < nr_slots(alloc_size + offset); i++)
mem->slots[index + i].orig_addr = slot_addr(orig_addr, i);
- mem->slots[index + i].alloc_size =
- alloc_size - (i << IO_TLB_SHIFT);
- }
tlb_addr = slot_addr(mem->start, index) + offset;
if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC) &&
(dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL))
--
2.32.0.272.g935e593368-goog
^ permalink raw reply related
* [PATCH v10 08/12] swiotlb: Refactor swiotlb_tbl_unmap_single
From: Claire Chang @ 2021-06-15 13:27 UTC (permalink / raw)
To: Rob Herring, mpe, Joerg Roedel, Will Deacon, Frank Rowand,
Konrad Rzeszutek Wilk, boris.ostrovsky, jgross, Christoph Hellwig,
Marek Szyprowski
Cc: heikki.krogerus, thomas.hellstrom, peterz, joonas.lahtinen,
dri-devel, chris, grant.likely, paulus, mingo, jxgao, sstabellini,
Saravana Kannan, xypron.glpk, Rafael J . Wysocki,
Bartosz Golaszewski, bskeggs, linux-pci, xen-devel,
Thierry Reding, intel-gfx, matthew.auld, linux-devicetree, daniel,
airlied, maarten.lankhorst, linuxppc-dev, jani.nikula,
Nicolas Boichat, rodrigo.vivi, bhelgaas, tientzu, Dan Williams,
Andy Shevchenko, Greg KH, Randy Dunlap, lkml, tfiga,
list@263.net:IOMMU DRIVERS, Jim Quinlan, Robin Murphy, bauerman
In-Reply-To: <20210615132711.553451-1-tientzu@chromium.org>
Add a new function, swiotlb_release_slots, to make the code reusable for
supporting different bounce buffer pools.
Signed-off-by: Claire Chang <tientzu@chromium.org>
---
kernel/dma/swiotlb.c | 35 ++++++++++++++++++++---------------
1 file changed, 20 insertions(+), 15 deletions(-)
diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
index e498f11e150e..3c01162c400b 100644
--- a/kernel/dma/swiotlb.c
+++ b/kernel/dma/swiotlb.c
@@ -546,27 +546,15 @@ phys_addr_t swiotlb_tbl_map_single(struct device *dev, phys_addr_t orig_addr,
return tlb_addr;
}
-/*
- * tlb_addr is the physical address of the bounce buffer to unmap.
- */
-void swiotlb_tbl_unmap_single(struct device *hwdev, phys_addr_t tlb_addr,
- size_t mapping_size, enum dma_data_direction dir,
- unsigned long attrs)
+static void swiotlb_release_slots(struct device *dev, phys_addr_t tlb_addr)
{
- struct io_tlb_mem *mem = hwdev->dma_io_tlb_mem;
+ struct io_tlb_mem *mem = dev->dma_io_tlb_mem;
unsigned long flags;
- unsigned int offset = swiotlb_align_offset(hwdev, tlb_addr);
+ unsigned int offset = swiotlb_align_offset(dev, tlb_addr);
int index = (tlb_addr - offset - mem->start) >> IO_TLB_SHIFT;
int nslots = nr_slots(mem->slots[index].alloc_size + offset);
int count, i;
- /*
- * First, sync the memory before unmapping the entry
- */
- if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC) &&
- (dir == DMA_FROM_DEVICE || dir == DMA_BIDIRECTIONAL))
- swiotlb_bounce(hwdev, tlb_addr, mapping_size, DMA_FROM_DEVICE);
-
/*
* Return the buffer to the free list by setting the corresponding
* entries to indicate the number of contiguous entries available.
@@ -601,6 +589,23 @@ void swiotlb_tbl_unmap_single(struct device *hwdev, phys_addr_t tlb_addr,
spin_unlock_irqrestore(&mem->lock, flags);
}
+/*
+ * tlb_addr is the physical address of the bounce buffer to unmap.
+ */
+void swiotlb_tbl_unmap_single(struct device *dev, phys_addr_t tlb_addr,
+ size_t mapping_size, enum dma_data_direction dir,
+ unsigned long attrs)
+{
+ /*
+ * First, sync the memory before unmapping the entry
+ */
+ if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC) &&
+ (dir == DMA_FROM_DEVICE || dir == DMA_BIDIRECTIONAL))
+ swiotlb_bounce(dev, tlb_addr, mapping_size, DMA_FROM_DEVICE);
+
+ swiotlb_release_slots(dev, tlb_addr);
+}
+
void swiotlb_sync_single_for_device(struct device *dev, phys_addr_t tlb_addr,
size_t size, enum dma_data_direction dir)
{
--
2.32.0.272.g935e593368-goog
^ permalink raw reply related
* [PATCH v10 09/12] swiotlb: Add restricted DMA pool initialization
From: Claire Chang @ 2021-06-15 13:27 UTC (permalink / raw)
To: Rob Herring, mpe, Joerg Roedel, Will Deacon, Frank Rowand,
Konrad Rzeszutek Wilk, boris.ostrovsky, jgross, Christoph Hellwig,
Marek Szyprowski
Cc: heikki.krogerus, thomas.hellstrom, peterz, joonas.lahtinen,
dri-devel, chris, grant.likely, paulus, mingo, jxgao, sstabellini,
Saravana Kannan, xypron.glpk, Rafael J . Wysocki,
Bartosz Golaszewski, bskeggs, linux-pci, xen-devel,
Thierry Reding, intel-gfx, matthew.auld, linux-devicetree, daniel,
airlied, maarten.lankhorst, linuxppc-dev, jani.nikula,
Nicolas Boichat, rodrigo.vivi, bhelgaas, tientzu, Dan Williams,
Andy Shevchenko, Greg KH, Randy Dunlap, lkml, tfiga,
list@263.net:IOMMU DRIVERS, Jim Quinlan, Robin Murphy, bauerman
In-Reply-To: <20210615132711.553451-1-tientzu@chromium.org>
Add the initialization function to create restricted DMA pools from
matching reserved-memory nodes.
Regardless of swiotlb setting, the restricted DMA pool is preferred if
available.
The restricted DMA pools provide a basic level of protection against the
DMA overwriting buffer contents at unexpected times. However, to protect
against general data leakage and system memory corruption, the system
needs to provide a way to lock down the memory access, e.g., MPU.
Signed-off-by: Claire Chang <tientzu@chromium.org>
---
include/linux/swiotlb.h | 3 +-
kernel/dma/Kconfig | 14 ++++++++
kernel/dma/swiotlb.c | 78 +++++++++++++++++++++++++++++++++++++++++
3 files changed, 94 insertions(+), 1 deletion(-)
diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h
index efcd56e3a16c..e76ac46ffff9 100644
--- a/include/linux/swiotlb.h
+++ b/include/linux/swiotlb.h
@@ -73,7 +73,8 @@ extern enum swiotlb_force swiotlb_force;
* range check to see if the memory was in fact allocated by this
* API.
* @nslabs: The number of IO TLB blocks (in groups of 64) between @start and
- * @end. This is command line adjustable via setup_io_tlb_npages.
+ * @end. For default swiotlb, this is command line adjustable via
+ * setup_io_tlb_npages.
* @used: The number of used IO TLB block.
* @list: The free list describing the number of free entries available
* from each index.
diff --git a/kernel/dma/Kconfig b/kernel/dma/Kconfig
index 77b405508743..3e961dc39634 100644
--- a/kernel/dma/Kconfig
+++ b/kernel/dma/Kconfig
@@ -80,6 +80,20 @@ config SWIOTLB
bool
select NEED_DMA_MAP_STATE
+config DMA_RESTRICTED_POOL
+ bool "DMA Restricted Pool"
+ depends on OF && OF_RESERVED_MEM
+ select SWIOTLB
+ help
+ This enables support for restricted DMA pools which provide a level of
+ DMA memory protection on systems with limited hardware protection
+ capabilities, such as those lacking an IOMMU.
+
+ For more information see
+ <Documentation/devicetree/bindings/reserved-memory/reserved-memory.txt>
+ and <kernel/dma/swiotlb.c>.
+ If unsure, say "n".
+
#
# Should be selected if we can mmap non-coherent mappings to userspace.
# The only thing that is really required is a way to set an uncached bit
diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
index 3c01162c400b..ef1ccd63534d 100644
--- a/kernel/dma/swiotlb.c
+++ b/kernel/dma/swiotlb.c
@@ -39,6 +39,13 @@
#ifdef CONFIG_DEBUG_FS
#include <linux/debugfs.h>
#endif
+#ifdef CONFIG_DMA_RESTRICTED_POOL
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_fdt.h>
+#include <linux/of_reserved_mem.h>
+#include <linux/slab.h>
+#endif
#include <asm/io.h>
#include <asm/dma.h>
@@ -693,3 +700,74 @@ static int __init swiotlb_create_default_debugfs(void)
late_initcall(swiotlb_create_default_debugfs);
#endif
+
+#ifdef CONFIG_DMA_RESTRICTED_POOL
+static int rmem_swiotlb_device_init(struct reserved_mem *rmem,
+ struct device *dev)
+{
+ struct io_tlb_mem *mem = rmem->priv;
+ unsigned long nslabs = rmem->size >> IO_TLB_SHIFT;
+
+ /*
+ * Since multiple devices can share the same pool, the private data,
+ * io_tlb_mem struct, will be initialized by the first device attached
+ * to it.
+ */
+ if (!mem) {
+ mem = kzalloc(struct_size(mem, slots, nslabs), GFP_KERNEL);
+ if (!mem)
+ return -ENOMEM;
+
+ swiotlb_init_io_tlb_mem(mem, rmem->base, nslabs, false);
+ mem->force = true;
+ set_memory_decrypted((unsigned long)phys_to_virt(rmem->base),
+ rmem->size >> PAGE_SHIFT);
+
+ rmem->priv = mem;
+
+ if (IS_ENABLED(CONFIG_DEBUG_FS)) {
+ mem->debugfs =
+ debugfs_create_dir(rmem->name, debugfs_dir);
+ swiotlb_create_debugfs_files(mem);
+ }
+ }
+
+ dev->dma_io_tlb_mem = mem;
+
+ return 0;
+}
+
+static void rmem_swiotlb_device_release(struct reserved_mem *rmem,
+ struct device *dev)
+{
+ dev->dma_io_tlb_mem = io_tlb_default_mem;
+}
+
+static const struct reserved_mem_ops rmem_swiotlb_ops = {
+ .device_init = rmem_swiotlb_device_init,
+ .device_release = rmem_swiotlb_device_release,
+};
+
+static int __init rmem_swiotlb_setup(struct reserved_mem *rmem)
+{
+ unsigned long node = rmem->fdt_node;
+
+ if (of_get_flat_dt_prop(node, "reusable", NULL) ||
+ of_get_flat_dt_prop(node, "linux,cma-default", NULL) ||
+ of_get_flat_dt_prop(node, "linux,dma-default", NULL) ||
+ of_get_flat_dt_prop(node, "no-map", NULL))
+ return -EINVAL;
+
+ if (PageHighMem(pfn_to_page(PHYS_PFN(rmem->base)))) {
+ pr_err("Restricted DMA pool must be accessible within the linear mapping.");
+ return -EINVAL;
+ }
+
+ rmem->ops = &rmem_swiotlb_ops;
+ pr_info("Reserved memory: created restricted DMA pool at %pa, size %ld MiB\n",
+ &rmem->base, (unsigned long)rmem->size / SZ_1M);
+ return 0;
+}
+
+RESERVEDMEM_OF_DECLARE(dma, "restricted-dma-pool", rmem_swiotlb_setup);
+#endif /* CONFIG_DMA_RESTRICTED_POOL */
--
2.32.0.272.g935e593368-goog
^ permalink raw reply related
* [PATCH 07/18] bvec: add memcpy_{from, to}_bvec and memzero_bvec helper
From: Christoph Hellwig @ 2021-06-15 13:24 UTC (permalink / raw)
To: Jens Axboe, Thomas Gleixner
Cc: linux-arch, linux-block, Thomas Bogendoerfer, Chaitanya Kulkarni,
Mike Snitzer, Geoff Levand, linuxppc-dev, linux-mips,
Dongsheng Yang, linux-kernel, James E.J. Bottomley, dm-devel,
Ilya Dryomov, Ira Weiny, ceph-devel
In-Reply-To: <20210615132456.753241-1-hch@lst.de>
Add helpers to perform common memory operation on a bvec.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
---
include/linux/bvec.h | 33 +++++++++++++++++++++++++++++++++
1 file changed, 33 insertions(+)
diff --git a/include/linux/bvec.h b/include/linux/bvec.h
index f8710af18eef..f9fa43b940ff 100644
--- a/include/linux/bvec.h
+++ b/include/linux/bvec.h
@@ -196,4 +196,37 @@ static inline void *bvec_kmap_local(struct bio_vec *bvec)
return kmap_local_page(bvec->bv_page) + bvec->bv_offset;
}
+/**
+ * memcpy_from_bvec - copy data from a bvec
+ * @bvec: bvec to copy from
+ *
+ * Must be called on single-page bvecs only.
+ */
+static inline void memcpy_from_bvec(char *to, struct bio_vec *bvec)
+{
+ memcpy_from_page(to, bvec->bv_page, bvec->bv_offset, bvec->bv_len);
+}
+
+/**
+ * memcpy_to_bvec - copy data to a bvec
+ * @bvec: bvec to copy to
+ *
+ * Must be called on single-page bvecs only.
+ */
+static inline void memcpy_to_bvec(struct bio_vec *bvec, const char *from)
+{
+ memcpy_to_page(bvec->bv_page, bvec->bv_offset, from, bvec->bv_len);
+}
+
+/**
+ * memzero_bvec - zero all data in a bvec
+ * @bvec: bvec to zero
+ *
+ * Must be called on single-page bvecs only.
+ */
+static inline void memzero_bvec(struct bio_vec *bvec)
+{
+ memzero_page(bvec->bv_page, bvec->bv_offset, bvec->bv_len);
+}
+
#endif /* __LINUX_BVEC_H */
--
2.30.2
^ permalink raw reply related
* [PATCH v10 10/12] swiotlb: Add restricted DMA alloc/free support
From: Claire Chang @ 2021-06-15 13:27 UTC (permalink / raw)
To: Rob Herring, mpe, Joerg Roedel, Will Deacon, Frank Rowand,
Konrad Rzeszutek Wilk, boris.ostrovsky, jgross, Christoph Hellwig,
Marek Szyprowski
Cc: heikki.krogerus, thomas.hellstrom, peterz, joonas.lahtinen,
dri-devel, chris, grant.likely, paulus, mingo, jxgao, sstabellini,
Saravana Kannan, xypron.glpk, Rafael J . Wysocki,
Bartosz Golaszewski, bskeggs, linux-pci, xen-devel,
Thierry Reding, intel-gfx, matthew.auld, linux-devicetree, daniel,
airlied, maarten.lankhorst, linuxppc-dev, jani.nikula,
Nicolas Boichat, rodrigo.vivi, bhelgaas, tientzu, Dan Williams,
Andy Shevchenko, Greg KH, Randy Dunlap, lkml, tfiga,
list@263.net:IOMMU DRIVERS, Jim Quinlan, Robin Murphy, bauerman
In-Reply-To: <20210615132711.553451-1-tientzu@chromium.org>
Add the functions, swiotlb_{alloc,free} to support the memory allocation
from restricted DMA pool.
The restricted DMA pool is preferred if available.
Note that since coherent allocation needs remapping, one must set up
another device coherent pool by shared-dma-pool and use
dma_alloc_from_dev_coherent instead for atomic coherent allocation.
Signed-off-by: Claire Chang <tientzu@chromium.org>
---
include/linux/swiotlb.h | 15 +++++++++++++
kernel/dma/direct.c | 50 ++++++++++++++++++++++++++++++-----------
kernel/dma/swiotlb.c | 42 ++++++++++++++++++++++++++++++++--
3 files changed, 92 insertions(+), 15 deletions(-)
diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h
index e76ac46ffff9..9616346b727f 100644
--- a/include/linux/swiotlb.h
+++ b/include/linux/swiotlb.h
@@ -157,4 +157,19 @@ static inline void swiotlb_adjust_size(unsigned long size)
extern void swiotlb_print_info(void);
extern void swiotlb_set_max_segment(unsigned int);
+#ifdef CONFIG_DMA_RESTRICTED_POOL
+struct page *swiotlb_alloc(struct device *dev, size_t size);
+bool swiotlb_free(struct device *dev, struct page *page, size_t size);
+#else
+static inline struct page *swiotlb_alloc(struct device *dev, size_t size)
+{
+ return NULL;
+}
+static inline bool swiotlb_free(struct device *dev, struct page *page,
+ size_t size)
+{
+ return false;
+}
+#endif /* CONFIG_DMA_RESTRICTED_POOL */
+
#endif /* __LINUX_SWIOTLB_H */
diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c
index 3713461d6fe0..da0e09621230 100644
--- a/kernel/dma/direct.c
+++ b/kernel/dma/direct.c
@@ -75,6 +75,15 @@ static bool dma_coherent_ok(struct device *dev, phys_addr_t phys, size_t size)
min_not_zero(dev->coherent_dma_mask, dev->bus_dma_limit);
}
+static void __dma_direct_free_pages(struct device *dev, struct page *page,
+ size_t size)
+{
+ if (IS_ENABLED(CONFIG_DMA_RESTRICTED_POOL) &&
+ swiotlb_free(dev, page, size))
+ return;
+ dma_free_contiguous(dev, page, size);
+}
+
static struct page *__dma_direct_alloc_pages(struct device *dev, size_t size,
gfp_t gfp)
{
@@ -86,7 +95,16 @@ static struct page *__dma_direct_alloc_pages(struct device *dev, size_t size,
gfp |= dma_direct_optimal_gfp_mask(dev, dev->coherent_dma_mask,
&phys_limit);
- page = dma_alloc_contiguous(dev, size, gfp);
+ if (IS_ENABLED(CONFIG_DMA_RESTRICTED_POOL)) {
+ page = swiotlb_alloc(dev, size);
+ if (page && !dma_coherent_ok(dev, page_to_phys(page), size)) {
+ __dma_direct_free_pages(dev, page, size);
+ return NULL;
+ }
+ }
+
+ if (!page)
+ page = dma_alloc_contiguous(dev, size, gfp);
if (page && !dma_coherent_ok(dev, page_to_phys(page), size)) {
dma_free_contiguous(dev, page, size);
page = NULL;
@@ -142,7 +160,7 @@ void *dma_direct_alloc(struct device *dev, size_t size,
gfp |= __GFP_NOWARN;
if ((attrs & DMA_ATTR_NO_KERNEL_MAPPING) &&
- !force_dma_unencrypted(dev)) {
+ !force_dma_unencrypted(dev) && !is_dev_swiotlb_force(dev)) {
page = __dma_direct_alloc_pages(dev, size, gfp & ~__GFP_ZERO);
if (!page)
return NULL;
@@ -155,18 +173,23 @@ void *dma_direct_alloc(struct device *dev, size_t size,
}
if (!IS_ENABLED(CONFIG_ARCH_HAS_DMA_SET_UNCACHED) &&
- !IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) &&
- !dev_is_dma_coherent(dev))
+ !IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) && !dev_is_dma_coherent(dev) &&
+ !is_dev_swiotlb_force(dev))
return arch_dma_alloc(dev, size, dma_handle, gfp, attrs);
/*
* Remapping or decrypting memory may block. If either is required and
* we can't block, allocate the memory from the atomic pools.
+ * If restricted DMA (i.e., is_dev_swiotlb_force) is required, one must
+ * set up another device coherent pool by shared-dma-pool and use
+ * dma_alloc_from_dev_coherent instead.
*/
if (IS_ENABLED(CONFIG_DMA_COHERENT_POOL) &&
!gfpflags_allow_blocking(gfp) &&
(force_dma_unencrypted(dev) ||
- (IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) && !dev_is_dma_coherent(dev))))
+ (IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) &&
+ !dev_is_dma_coherent(dev))) &&
+ !is_dev_swiotlb_force(dev))
return dma_direct_alloc_from_pool(dev, size, dma_handle, gfp);
/* we always manually zero the memory once we are done */
@@ -237,7 +260,7 @@ void *dma_direct_alloc(struct device *dev, size_t size,
return NULL;
}
out_free_pages:
- dma_free_contiguous(dev, page, size);
+ __dma_direct_free_pages(dev, page, size);
return NULL;
}
@@ -247,15 +270,15 @@ void dma_direct_free(struct device *dev, size_t size,
unsigned int page_order = get_order(size);
if ((attrs & DMA_ATTR_NO_KERNEL_MAPPING) &&
- !force_dma_unencrypted(dev)) {
+ !force_dma_unencrypted(dev) && !is_dev_swiotlb_force(dev)) {
/* cpu_addr is a struct page cookie, not a kernel address */
dma_free_contiguous(dev, cpu_addr, size);
return;
}
if (!IS_ENABLED(CONFIG_ARCH_HAS_DMA_SET_UNCACHED) &&
- !IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) &&
- !dev_is_dma_coherent(dev)) {
+ !IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) && !dev_is_dma_coherent(dev) &&
+ !is_dev_swiotlb_force(dev)) {
arch_dma_free(dev, size, cpu_addr, dma_addr, attrs);
return;
}
@@ -273,7 +296,7 @@ void dma_direct_free(struct device *dev, size_t size,
else if (IS_ENABLED(CONFIG_ARCH_HAS_DMA_CLEAR_UNCACHED))
arch_dma_clear_uncached(cpu_addr, size);
- dma_free_contiguous(dev, dma_direct_to_page(dev, dma_addr), size);
+ __dma_direct_free_pages(dev, dma_direct_to_page(dev, dma_addr), size);
}
struct page *dma_direct_alloc_pages(struct device *dev, size_t size,
@@ -283,7 +306,8 @@ struct page *dma_direct_alloc_pages(struct device *dev, size_t size,
void *ret;
if (IS_ENABLED(CONFIG_DMA_COHERENT_POOL) &&
- force_dma_unencrypted(dev) && !gfpflags_allow_blocking(gfp))
+ force_dma_unencrypted(dev) && !gfpflags_allow_blocking(gfp) &&
+ !is_dev_swiotlb_force(dev))
return dma_direct_alloc_from_pool(dev, size, dma_handle, gfp);
page = __dma_direct_alloc_pages(dev, size, gfp);
@@ -310,7 +334,7 @@ struct page *dma_direct_alloc_pages(struct device *dev, size_t size,
*dma_handle = phys_to_dma_direct(dev, page_to_phys(page));
return page;
out_free_pages:
- dma_free_contiguous(dev, page, size);
+ __dma_direct_free_pages(dev, page, size);
return NULL;
}
@@ -329,7 +353,7 @@ void dma_direct_free_pages(struct device *dev, size_t size,
if (force_dma_unencrypted(dev))
set_memory_encrypted((unsigned long)vaddr, 1 << page_order);
- dma_free_contiguous(dev, page, size);
+ __dma_direct_free_pages(dev, page, size);
}
#if defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_DEVICE) || \
diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
index ef1ccd63534d..5e277eb65f92 100644
--- a/kernel/dma/swiotlb.c
+++ b/kernel/dma/swiotlb.c
@@ -460,8 +460,9 @@ static int swiotlb_find_slots(struct device *dev, phys_addr_t orig_addr,
index = wrap = wrap_index(mem, ALIGN(mem->index, stride));
do {
- if ((slot_addr(tbl_dma_addr, index) & iotlb_align_mask) !=
- (orig_addr & iotlb_align_mask)) {
+ if (orig_addr &&
+ (slot_addr(tbl_dma_addr, index) & iotlb_align_mask) !=
+ (orig_addr & iotlb_align_mask)) {
index = wrap_index(mem, index + 1);
continue;
}
@@ -702,6 +703,43 @@ late_initcall(swiotlb_create_default_debugfs);
#endif
#ifdef CONFIG_DMA_RESTRICTED_POOL
+struct page *swiotlb_alloc(struct device *dev, size_t size)
+{
+ struct io_tlb_mem *mem = dev->dma_io_tlb_mem;
+ phys_addr_t tlb_addr;
+ int index;
+
+ /*
+ * Skip io_tlb_default_mem since swiotlb_alloc doesn't support atomic
+ * coherent allocation. Otherwise might break existing devices.
+ * One must set up another device coherent pool by shared-dma-pool and
+ * use dma_alloc_from_dev_coherent instead for atomic coherent
+ * allocation to avoid mempry remapping.
+ */
+ if (!mem || mem == io_tlb_default_mem)
+ return NULL;
+
+ index = swiotlb_find_slots(dev, 0, size);
+ if (index == -1)
+ return NULL;
+
+ tlb_addr = slot_addr(mem->start, index);
+
+ return pfn_to_page(PFN_DOWN(tlb_addr));
+}
+
+bool swiotlb_free(struct device *dev, struct page *page, size_t size)
+{
+ phys_addr_t tlb_addr = page_to_phys(page);
+
+ if (!is_swiotlb_buffer(dev, tlb_addr))
+ return false;
+
+ swiotlb_release_slots(dev, tlb_addr);
+
+ return true;
+}
+
static int rmem_swiotlb_device_init(struct reserved_mem *rmem,
struct device *dev)
{
--
2.32.0.272.g935e593368-goog
^ permalink raw reply related
* [PATCH v10 11/12] dt-bindings: of: Add restricted DMA pool
From: Claire Chang @ 2021-06-15 13:27 UTC (permalink / raw)
To: Rob Herring, mpe, Joerg Roedel, Will Deacon, Frank Rowand,
Konrad Rzeszutek Wilk, boris.ostrovsky, jgross, Christoph Hellwig,
Marek Szyprowski
Cc: heikki.krogerus, thomas.hellstrom, peterz, joonas.lahtinen,
dri-devel, chris, grant.likely, paulus, mingo, jxgao, sstabellini,
Saravana Kannan, xypron.glpk, Rafael J . Wysocki,
Bartosz Golaszewski, bskeggs, linux-pci, xen-devel,
Thierry Reding, intel-gfx, matthew.auld, linux-devicetree, daniel,
airlied, maarten.lankhorst, linuxppc-dev, jani.nikula,
Nicolas Boichat, rodrigo.vivi, bhelgaas, tientzu, Dan Williams,
Andy Shevchenko, Greg KH, Randy Dunlap, lkml, tfiga,
list@263.net:IOMMU DRIVERS, Jim Quinlan, Robin Murphy, bauerman
In-Reply-To: <20210615132711.553451-1-tientzu@chromium.org>
Introduce the new compatible string, restricted-dma-pool, for restricted
DMA. One can specify the address and length of the restricted DMA memory
region by restricted-dma-pool in the reserved-memory node.
Signed-off-by: Claire Chang <tientzu@chromium.org>
---
.../reserved-memory/reserved-memory.txt | 36 +++++++++++++++++--
1 file changed, 33 insertions(+), 3 deletions(-)
diff --git a/Documentation/devicetree/bindings/reserved-memory/reserved-memory.txt b/Documentation/devicetree/bindings/reserved-memory/reserved-memory.txt
index e8d3096d922c..46804f24df05 100644
--- a/Documentation/devicetree/bindings/reserved-memory/reserved-memory.txt
+++ b/Documentation/devicetree/bindings/reserved-memory/reserved-memory.txt
@@ -51,6 +51,23 @@ compatible (optional) - standard definition
used as a shared pool of DMA buffers for a set of devices. It can
be used by an operating system to instantiate the necessary pool
management subsystem if necessary.
+ - restricted-dma-pool: This indicates a region of memory meant to be
+ used as a pool of restricted DMA buffers for a set of devices. The
+ memory region would be the only region accessible to those devices.
+ When using this, the no-map and reusable properties must not be set,
+ so the operating system can create a virtual mapping that will be used
+ for synchronization. The main purpose for restricted DMA is to
+ mitigate the lack of DMA access control on systems without an IOMMU,
+ which could result in the DMA accessing the system memory at
+ unexpected times and/or unexpected addresses, possibly leading to data
+ leakage or corruption. The feature on its own provides a basic level
+ of protection against the DMA overwriting buffer contents at
+ unexpected times. However, to protect against general data leakage and
+ system memory corruption, the system needs to provide way to lock down
+ the memory access, e.g., MPU. Note that since coherent allocation
+ needs remapping, one must set up another device coherent pool by
+ shared-dma-pool and use dma_alloc_from_dev_coherent instead for atomic
+ coherent allocation.
- vendor specific string in the form <vendor>,[<device>-]<usage>
no-map (optional) - empty property
- Indicates the operating system must not create a virtual mapping
@@ -85,10 +102,11 @@ memory-region-names (optional) - a list of names, one for each corresponding
Example
-------
-This example defines 3 contiguous regions are defined for Linux kernel:
+This example defines 4 contiguous regions for Linux kernel:
one default of all device drivers (named linux,cma@72000000 and 64MiB in size),
-one dedicated to the framebuffer device (named framebuffer@78000000, 8MiB), and
-one for multimedia processing (named multimedia-memory@77000000, 64MiB).
+one dedicated to the framebuffer device (named framebuffer@78000000, 8MiB),
+one for multimedia processing (named multimedia-memory@77000000, 64MiB), and
+one for restricted dma pool (named restricted_dma_reserved@0x50000000, 64MiB).
/ {
#address-cells = <1>;
@@ -120,6 +138,11 @@ one for multimedia processing (named multimedia-memory@77000000, 64MiB).
compatible = "acme,multimedia-memory";
reg = <0x77000000 0x4000000>;
};
+
+ restricted_dma_reserved: restricted_dma_reserved {
+ compatible = "restricted-dma-pool";
+ reg = <0x50000000 0x4000000>;
+ };
};
/* ... */
@@ -138,4 +161,11 @@ one for multimedia processing (named multimedia-memory@77000000, 64MiB).
memory-region = <&multimedia_reserved>;
/* ... */
};
+
+ pcie_device: pcie_device@0,0 {
+ reg = <0x83010000 0x0 0x00000000 0x0 0x00100000
+ 0x83010000 0x0 0x00100000 0x0 0x00100000>;
+ memory-region = <&restricted_dma_mem_reserved>;
+ /* ... */
+ };
};
--
2.32.0.272.g935e593368-goog
^ permalink raw reply related
* [PATCH v10 12/12] of: Add plumbing for restricted DMA pool
From: Claire Chang @ 2021-06-15 13:27 UTC (permalink / raw)
To: Rob Herring, mpe, Joerg Roedel, Will Deacon, Frank Rowand,
Konrad Rzeszutek Wilk, boris.ostrovsky, jgross, Christoph Hellwig,
Marek Szyprowski
Cc: heikki.krogerus, thomas.hellstrom, peterz, joonas.lahtinen,
dri-devel, chris, grant.likely, paulus, mingo, jxgao, sstabellini,
Saravana Kannan, xypron.glpk, Rafael J . Wysocki,
Bartosz Golaszewski, bskeggs, linux-pci, xen-devel,
Thierry Reding, intel-gfx, matthew.auld, linux-devicetree, daniel,
airlied, maarten.lankhorst, linuxppc-dev, jani.nikula,
Nicolas Boichat, rodrigo.vivi, bhelgaas, tientzu, Dan Williams,
Andy Shevchenko, Greg KH, Randy Dunlap, lkml, tfiga,
list@263.net:IOMMU DRIVERS, Jim Quinlan, Robin Murphy, bauerman
In-Reply-To: <20210615132711.553451-1-tientzu@chromium.org>
If a device is not behind an IOMMU, we look up the device node and set
up the restricted DMA when the restricted-dma-pool is presented.
Signed-off-by: Claire Chang <tientzu@chromium.org>
---
drivers/of/address.c | 33 +++++++++++++++++++++++++++++++++
drivers/of/device.c | 3 +++
drivers/of/of_private.h | 6 ++++++
3 files changed, 42 insertions(+)
diff --git a/drivers/of/address.c b/drivers/of/address.c
index 3b2acca7e363..c8066d95ff0e 100644
--- a/drivers/of/address.c
+++ b/drivers/of/address.c
@@ -8,6 +8,7 @@
#include <linux/logic_pio.h>
#include <linux/module.h>
#include <linux/of_address.h>
+#include <linux/of_reserved_mem.h>
#include <linux/pci.h>
#include <linux/pci_regs.h>
#include <linux/sizes.h>
@@ -1001,6 +1002,38 @@ int of_dma_get_range(struct device_node *np, const struct bus_dma_region **map)
of_node_put(node);
return ret;
}
+
+int of_dma_set_restricted_buffer(struct device *dev, struct device_node *np)
+{
+ struct device_node *node, *of_node = dev->of_node;
+ int count, i;
+
+ count = of_property_count_elems_of_size(of_node, "memory-region",
+ sizeof(u32));
+ /*
+ * If dev->of_node doesn't exist or doesn't contain memory-region, try
+ * the OF node having DMA configuration.
+ */
+ if (count <= 0) {
+ of_node = np;
+ count = of_property_count_elems_of_size(
+ of_node, "memory-region", sizeof(u32));
+ }
+
+ for (i = 0; i < count; i++) {
+ node = of_parse_phandle(of_node, "memory-region", i);
+ /*
+ * There might be multiple memory regions, but only one
+ * restricted-dma-pool region is allowed.
+ */
+ if (of_device_is_compatible(node, "restricted-dma-pool") &&
+ of_device_is_available(node))
+ return of_reserved_mem_device_init_by_idx(dev, of_node,
+ i);
+ }
+
+ return 0;
+}
#endif /* CONFIG_HAS_DMA */
/**
diff --git a/drivers/of/device.c b/drivers/of/device.c
index c5a9473a5fb1..2defdca418ec 100644
--- a/drivers/of/device.c
+++ b/drivers/of/device.c
@@ -165,6 +165,9 @@ int of_dma_configure_id(struct device *dev, struct device_node *np,
arch_setup_dma_ops(dev, dma_start, size, iommu, coherent);
+ if (!iommu)
+ return of_dma_set_restricted_buffer(dev, np);
+
return 0;
}
EXPORT_SYMBOL_GPL(of_dma_configure_id);
diff --git a/drivers/of/of_private.h b/drivers/of/of_private.h
index 631489f7f8c0..376462798f7e 100644
--- a/drivers/of/of_private.h
+++ b/drivers/of/of_private.h
@@ -163,12 +163,18 @@ struct bus_dma_region;
#if defined(CONFIG_OF_ADDRESS) && defined(CONFIG_HAS_DMA)
int of_dma_get_range(struct device_node *np,
const struct bus_dma_region **map);
+int of_dma_set_restricted_buffer(struct device *dev, struct device_node *np);
#else
static inline int of_dma_get_range(struct device_node *np,
const struct bus_dma_region **map)
{
return -ENODEV;
}
+static inline int of_dma_set_restricted_buffer(struct device *dev,
+ struct device_node *np)
+{
+ return -ENODEV;
+}
#endif
void fdt_init_reserved_mem(void);
--
2.32.0.272.g935e593368-goog
^ permalink raw reply related
* [PATCH 08/18] block: use memzero_page in zero_fill_bio
From: Christoph Hellwig @ 2021-06-15 13:24 UTC (permalink / raw)
To: Jens Axboe, Thomas Gleixner
Cc: linux-arch, linux-block, Thomas Bogendoerfer, Chaitanya Kulkarni,
Mike Snitzer, Geoff Levand, linuxppc-dev, linux-mips,
Dongsheng Yang, linux-kernel, James E.J. Bottomley, dm-devel,
Ilya Dryomov, Ira Weiny, ceph-devel
In-Reply-To: <20210615132456.753241-1-hch@lst.de>
Use memzero_bvec to zero each segment in the bio instead of manually
mapping and zeroing the data.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
---
block/bio.c | 9 ++-------
1 file changed, 2 insertions(+), 7 deletions(-)
diff --git a/block/bio.c b/block/bio.c
index 44205dfb6b60..1d7abdb83a39 100644
--- a/block/bio.c
+++ b/block/bio.c
@@ -495,16 +495,11 @@ EXPORT_SYMBOL(bio_kmalloc);
void zero_fill_bio(struct bio *bio)
{
- unsigned long flags;
struct bio_vec bv;
struct bvec_iter iter;
- bio_for_each_segment(bv, bio, iter) {
- char *data = bvec_kmap_irq(&bv, &flags);
- memset(data, 0, bv.bv_len);
- flush_dcache_page(bv.bv_page);
- bvec_kunmap_irq(data, &flags);
- }
+ bio_for_each_segment(bv, bio, iter)
+ memzero_bvec(&bv);
}
EXPORT_SYMBOL(zero_fill_bio);
--
2.30.2
^ permalink raw reply related
* [PATCH 09/18] rbd: use memzero_bvec
From: Christoph Hellwig @ 2021-06-15 13:24 UTC (permalink / raw)
To: Jens Axboe, Thomas Gleixner
Cc: linux-arch, linux-block, Thomas Bogendoerfer, Mike Snitzer,
Geoff Levand, linuxppc-dev, linux-mips, Dongsheng Yang,
linux-kernel, James E.J. Bottomley, dm-devel, Ilya Dryomov,
Ira Weiny, ceph-devel
In-Reply-To: <20210615132456.753241-1-hch@lst.de>
Use memzero_bvec instead of reimplementing it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
---
drivers/block/rbd.c | 15 ++-------------
1 file changed, 2 insertions(+), 13 deletions(-)
diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c
index 531d390902dd..501a10bfb1fe 100644
--- a/drivers/block/rbd.c
+++ b/drivers/block/rbd.c
@@ -1219,24 +1219,13 @@ static void rbd_dev_mapping_clear(struct rbd_device *rbd_dev)
rbd_dev->mapping.size = 0;
}
-static void zero_bvec(struct bio_vec *bv)
-{
- void *buf;
- unsigned long flags;
-
- buf = bvec_kmap_irq(bv, &flags);
- memset(buf, 0, bv->bv_len);
- flush_dcache_page(bv->bv_page);
- bvec_kunmap_irq(buf, &flags);
-}
-
static void zero_bios(struct ceph_bio_iter *bio_pos, u32 off, u32 bytes)
{
struct ceph_bio_iter it = *bio_pos;
ceph_bio_iter_advance(&it, off);
ceph_bio_iter_advance_step(&it, bytes, ({
- zero_bvec(&bv);
+ memzero_bvec(&bv);
}));
}
@@ -1246,7 +1235,7 @@ static void zero_bvecs(struct ceph_bvec_iter *bvec_pos, u32 off, u32 bytes)
ceph_bvec_iter_advance(&it, off);
ceph_bvec_iter_advance_step(&it, bytes, ({
- zero_bvec(&bv);
+ memzero_bvec(&bv);
}));
}
--
2.30.2
^ permalink raw reply related
* [PATCH 10/18] dm-writecache: use bvec_kmap_local instead of bvec_kmap_irq
From: Christoph Hellwig @ 2021-06-15 13:24 UTC (permalink / raw)
To: Jens Axboe, Thomas Gleixner
Cc: linux-arch, linux-block, Thomas Bogendoerfer, Mike Snitzer,
Geoff Levand, linuxppc-dev, linux-mips, Dongsheng Yang,
linux-kernel, James E.J. Bottomley, dm-devel, Ilya Dryomov,
Ira Weiny, ceph-devel
In-Reply-To: <20210615132456.753241-1-hch@lst.de>
There is no need to disable interrupts in bio_copy_block, and the local
only mappings helps to avoid any sort of problems with stray writes
into the bio data.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
---
drivers/md/dm-writecache.c | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)
diff --git a/drivers/md/dm-writecache.c b/drivers/md/dm-writecache.c
index aecc246ade26..93ca454eaca9 100644
--- a/drivers/md/dm-writecache.c
+++ b/drivers/md/dm-writecache.c
@@ -1205,14 +1205,13 @@ static void memcpy_flushcache_optimized(void *dest, void *source, size_t size)
static void bio_copy_block(struct dm_writecache *wc, struct bio *bio, void *data)
{
void *buf;
- unsigned long flags;
unsigned size;
int rw = bio_data_dir(bio);
unsigned remaining_size = wc->block_size;
do {
struct bio_vec bv = bio_iter_iovec(bio, bio->bi_iter);
- buf = bvec_kmap_irq(&bv, &flags);
+ buf = bvec_kmap_local(&bv);
size = bv.bv_len;
if (unlikely(size > remaining_size))
size = remaining_size;
@@ -1230,7 +1229,7 @@ static void bio_copy_block(struct dm_writecache *wc, struct bio *bio, void *data
memcpy_flushcache_optimized(data, buf, size);
}
- bvec_kunmap_irq(buf, &flags);
+ kunmap_local(buf);
data = (char *)data + size;
remaining_size -= size;
--
2.30.2
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